Quality Control

Each piece of Pacific States ductile iron pipe is manufactured to the strength/ductility designations 60-4210, meaning: 60,000 psi minimum ultimate strength, 42,000 psi minimum yield strength, and 10% minimum elongation,

Ductility, Strength, and Impact Resistance Testing

To ensure that our pipe meets the above characteristics, longitudinal specimens are cut from the midsections of the pipe wall during each casting period and subjected to the tensile test specified in ASTM Standard E8.

Control tests include the notched charpy impact test completed in accordance with ASTM Standard E23. Specimens are cut from the pipe wall and subjected to impact at 70° F ± 10°. A minimum acceptance value is 7 ft.-lb. Three impact tests are run each hour and typical results exceed 8 ft.-lb. Low temperature impact tests (-40°F) are accomplished on 10% of the sample coupons and must result in a minimum impact value of 3 ft.-lb.

Hydrostatic testing is accomplished with a length of ductile iron pipe secured in a test press. Five hundred psi internal water pressure is sustained for a minimum of 10 seconds to insure total pipe integrity.

Ductility of each pipe length is further checked by the ball impression test.

Results of all tests are logged and maintained in the foundry record. Table 1 lists quality control tests routinely completed at Pacific States. Users or potential users are encouraged to visit our foundry and observe the entire manufacturing and quality control processes.

Table 1

Ductile Iron Pipe Testing

Subject	Frequency	Information Recorded & Filed
Tensile Test	Each Casting Periodabout 3 hrs.	Yield; ultimate; % elongation. ANSI A21.51
Notched Charpy Test at 70°F	3 per hour	Ft/lb at 70°F ± 10° (7 ft/lb required) ANSI A21.51
Notched Charpy Test at -40°F	10% of 70° tests	Ft/lb at -40°F (3 ft/lb required) ANSI A21.51
Hydrostatic Test	Each pipe	Pressure-time (500 psi-10 sec. required) ANSI A21.51
Sand-Sieve Analysis	Daily	Grain fineness (Table 1, ANSI A21.4)
Sand-Colorimetric Test	Monthly	Record color change ASTM C40
Sand-Decantation Test	Monthly	Record % clay ASTM C117
Leaching Resistance	2 per week	Hardness; total alkalinity; caustic alkalinity ANSI A21.4
Seal Coat Material- Limit of Toxic Substances	Each shipment (about 3-month intervals)	Tests by supplier. ANSI A21.4 F.D.A. requirements
Taste and Odor	Monthly check for taste and odor on pipe exposed to distilled water for 24 hrs.	Independent panel rates taste and odor

Records Not Required by Standard but Used in Our Quality Control Procedures

Subject	Frequency	Information Recorded & Filed
Cement Analysis	Each Shipment	Tests by Supplier or Manufacturer
Water/Cement Ratio Mix, after spinning, and just before seal coating	Weekly or at times when changes are effected	Water-Cement ratio
Sand/Cement Ratio (mix)	Weekly or at change	Sand-Cement ratio
Spinning Rates and Vibration	Weekly or at times of change	g-forces applied. Pipe was vibrated-yes or no
Reaming	Weekly or at times of change	Yes or no
KMn04 Rinse	Weekly or at times of change	Yes or no
KMn04 in Mortar Mix	Weekly or at times of change	Yes or no
Tape Test	Daily	Passage or failure after 24 hrs. storage

Machinability

The ferrite in ductile iron pipe provides excellent machinability. Carbon within the matrix contributes to this feature, acting as a lubricant to cutting tools. Silicon improves the strength and wear resistance of the pipe but also helps its machinability by producing a cleaner cut. Thus, ductile iron pipe is ideal for field cutting and tapping both at the time of pipeline construction and during its entire service life.

Field cuts may be accomplished using an abrasive wheel, rotary wheel cutter, guillotine pipe saw or milling wheel. Cut ends should be ground smooth and for push-on joints, they should be beveled.

Ductile iron pipe in all diameters may be tapped for the installation of corporation stops in all classes without the use of tapping saddles. Required torque to effect a seal against high pressures may be lowered by the use of Teflon tape thread treatment. Exhaustive tests by the Ductile Iron Pipe Research Association have demonstrated that ductile iron threads are sufficiently strong to remain intact even if corporation stops are pulled out or broken by cantilever loads. During the tests, internal pressures exceeding the rated pressure of the pipe (350 psi) did not result in thread leaks.

Handling

No other pipe material offers resistance to construction handling equal to that of ductile iron pipe. Its high strength, impact resistance and ductility combine to support this very important advantage. Although Pacific States and AWWA Standard C600 stress careful handling, accidents do occur. Even severe impacts leave no damage beyond the immediate point of contact. If the pipe is dented, the cement-mortar lining should be checked and repaired if spalling has occurred. Should the spigot end be damaged, it can be cut off and beveled without loss of the pipe. Most projects using Pacific States ductile iron pipe are completed without any loss of pipe due to handling and construction damage.

Quality assurance extends through the shipping department where, along with our exclusive carrier, constant care is taken to see that the pipe reaches the job site on time and in mint condition.

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